RIGA, Sept. 30 (Xinhuanet) -- US warplanes started airspace patrol over the three Baltic states of Estonia, Latvia and Lithuania on Friday after taking over the NATO mission Friday from Germany.

At a ceremony held at the Zokniai Airbase in northern Lithuania,the country's Defense Minister Gediminas Kirkilas announced the NATO patrol succession.

Three US F-16 fighter jets arrived in Lithuania on Friday to be joined by another two Saturday to take off on patrol missions over the Baltic airspace. The mission involves almost 100 US servicemen,nearly doubling the number of NATO troops previously deployed in the country, according to reports reaching here.

US warplanes came two weeks after a Russian SU-27 fighter bomber crashed in Lithuania in September in violation of the country's airspace, triggering fear about NATO's capability of providing enough air protection.

The Russian SU-27 warplane was flying with other Russian jets from St. Petersburg to Russia's Baltic enclave of Kaliningrad through a neutral air corridor near the Lithuanian border. The plane deviated from its course, flew into Lithuanian airspace, andminutes later crashed into a field about 190 km northwest of the capital Vilnius. The Russian pilot ejected from the aircraft and was not injured.

Kirkilas believed the violation was not intentional. After tracking the plane by radar for six minutes, the Lithuanian military concluded that the pilot had lost direction and the planewas out of control, probably due to a malfunction of the plane's navigation system.

The Lithuanian defense chief also warned Friday that NATO countries must draw a lesson from the incident and that a decisionis needed on the issue of the kind.

He appreciated the US commitment to protecting the Baltic airspace at a due level.

Since their accession to the NATO alliance in March 2004, the airspace of the three Baltic states has been patrolled in turn by other NATO members, each for three months.

The NATO leadership has decided to prolong the patrol term to allow more time for patrol troops to familiarize themselves with the situation. Poland will become the first country to have a four-month term starting on Jan. 1, 2006.

So far, Belgium, Denmark, Britain, Norway, the Netherlands and Germany have completed their patrol missions. Enditem